Ɛpsilon

From Edward Frankland   27 September 1873

14 Lancaster Gate | Hyde Park W.

Sep. 27/73

My dear Sir

I have sent you per rail a Winchester quart of pure distilled water.1 It is difficult if not impossible to buy pure distilled water.

This has been subjected to the following operations

1. Freed from Ammonia

2. Distilled.

3. Boiled for 6 hours with Permangana⁠⟨⁠t⁠⟩⁠e of Potash2 to destroy organic matter

4. Distilled again.

When it is finished pray let me know & you shall have some more.

When I say it is pure you will of course still understand this in a relative sense. It still contains atmospheric gases in solution and a few zymotic germs in suspension.

Yours sincerely | E. Frankland

Charles Darwin Esq. F.R.S.

1
See letter to Edward Frankland, 23 September 1873. A Winchester quart in pharmacology is the equivalent of four imperial pints (OED); Winchester measures were standards for dry and liquid measures laid down at Winchester in the fifteenth century.
2
Permanganate of potash is now more commonly known as potassium permanganate; dissolved in water, it was used as a disinfectant and antiseptic.

Please cite as “DCP-LETT-9076,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-9076